HDR Display Output #22563

aevyrie · 2026-01-17T07:25:16Z

Objective

HDR support. Extra bright pixels.

Solution

Is it good? Probably not.
Is it passable? Who can say, really.
Everything I've read suggests this is really, really hard to do correctly. It might be nice to have an okay implementation we can iterate on to start.

Testing

cargo run --example hdr_calibration

Screen.Recording.2026-01-16.at.11.23.42.PM.mov

Screen.Recording.2026-01-17.at.1.02.37.AM.mov

# Conflicts: # crates/bevy_ui_render/Cargo.toml

github-actions · 2026-01-17T07:27:11Z

It looks like your PR has been selected for a highlight in the next release blog post, but you didn't provide a release note.

Please review the instructions for writing release notes, then expand or revise the content in the release notes directory to showcase your changes.

aevyrie · 2026-01-17T07:32:27Z

crates/bevy_core_pipeline/src/tonemapping/tonemapping_shared.wgsl

    return tonemapping_change_luminance(color, l_new);
 }

+fn tonemapping_pq(color: vec3<f32>, color_grading: ColorGrading) -> vec3<f32> {


I played with this a bit, needs love. Linear seems to just work ™️ on macOS.

github-actions · 2026-01-17T08:30:55Z

Your PR caused a change in the graphical output of an example or rendering test. This might be intentional, but it could also mean that something broke!
You can review it at https://pixel-eagle.com/project/B04F67C0-C054-4A6F-92EC-F599FEC2FD1D?filter=PR-22563

If it's expected, please add the M-Deliberate-Rendering-Change label.

If this change seems unrelated to your PR, you can consider updating your PR to target the latest main branch, either by rebasing or merging main into it.

johansigfrids · 2026-01-17T12:06:02Z

out_color = min(out_color, vec3(max_luminance_nits / 80.0));

Does this clip each channel independently?

For example having (1500, 1200, 500) clipped to max 1000 gives (1000, 1000, 500).

That would shift the hue since the color proportions change.

github-actions · 2026-01-19T04:36:29Z

Your PR caused a change in the graphical output of an example or rendering test. This might be intentional, but it could also mean that something broke!
You can review it at https://pixel-eagle.com/project/B04F67C0-C054-4A6F-92EC-F599FEC2FD1D?filter=PR-22563

If it's expected, please add the M-Deliberate-Rendering-Change label.

If this change seems unrelated to your PR, you can consider updating your PR to target the latest main branch, either by rebasing or merging main into it.

aevyrie · 2026-01-21T05:09:56Z

Seems to be working on Windows: https://discord.com/channels/691052431525675048/743663924229963868/1463398806363181097

jasmine-nominal

Initial review.

Some stuff still TODO for me:

Read up on HDR stuff again, it's been a while
Check if Pq is a good tonemapping method
Try across various displays, especially on windows/linux (linux HDR support is a little rough iirc)
Figure out how this interacts with color spaces/gamut
Figure out if we need anything from wgpu for this
Figure out how this work on WebGPU

Also question: How can users check at runtime if HDR is supported or not? Can you figure that out, and then add some text to the example for when HDR is not supported?

jasmine-nominal · 2026-01-21T16:07:21Z

crates/bevy_pbr/src/render/mesh.rs

        let mut view_key = MeshPipelineKey::from_msaa_samples(msaa.samples())
            | MeshPipelineKey::from_hdr(view.hdr);

+        if view.hdr_output {


I think we need the view key stuff in a lot more places? E.g. meshlet shading passes.

jasmine-nominal · 2026-01-21T16:08:33Z

crates/bevy_post_process/src/bloom/mod.rs

+    for (camera, mut uniforms, bloom) in &mut views {
+        uniforms.hdr_output = camera.hdr_output as u32;
+
+        if camera.hdr_output && bloom.prefilter.threshold == 0.0 {


What is this for?

jasmine-nominal · 2026-01-21T16:09:29Z

crates/bevy_post_process/src/bloom/upsampling_pipeline.rs

+            if key.hdr {
+                ViewTarget::TEXTURE_FORMAT_HDR
+            } else {
+                TextureFormat::bevy_default()


Wait why does bloom support non-floating point (HDR) internal textures now?

Also I would really like to rename HDR now...

jasmine-nominal · 2026-01-21T16:11:32Z

crates/bevy_render/src/view/window/mod.rs

-                        format = available_format;
-                        break;
+
+                if window.hdr_output {


Please abstract this out into a get_surface_format function.

jasmine-nominal · 2026-01-21T16:13:37Z

crates/bevy_render/src/view/window/mod.rs

+                if window.hdr_output {
+                    for available_format in &formats {
+                        if *available_format == TextureFormat::Rgba16Float {
+                            format = *available_format;


What about non-Rgba16Float HDR swapchain formats? Iirc some platforms/monitors/whatever only support other formats.

jasmine-nominal · 2026-01-21T16:14:19Z

crates/bevy_ui_render/src/box_shadow.rs

 #[derive(Clone, Copy, Hash, PartialEq, Eq)]
 pub struct BoxShadowPipelineKey {
    pub hdr: bool,
-    /// Number of samples, a higher value results in better quality shadows.


Comment was deleted.

jasmine-nominal · 2026-01-21T16:14:53Z

crates/bevy_ui_render/Cargo.toml

 ] }
 bevy_transform = { path = "../bevy_transform", version = "0.19.0-dev" }
 bevy_utils = { path = "../bevy_utils", version = "0.19.0-dev" }
+bevy_window = { path = "../bevy_window", version = "0.19.0-dev" }


@atlv24 is this ok?

jasmine-nominal · 2026-01-21T16:33:00Z

I don't really understand how to use the calibration example (am I supposed to google the values for my monitor?

Would it be better to implement something like this?

jasmine-nominal · 2026-01-21T16:33:52Z

Also, does putting the settings on ColorGrading make sense? Shouldn't they be per monitor somehow?

jasmine-nominal · 2026-01-21T16:35:54Z

The max luminance left/right controls in the demo seem inverted to how I expect.

jasmine-nominal · 2026-01-21T16:36:05Z

Is max luminance supposed to be sustained, or peak?

aevyrie · 2026-01-21T17:31:48Z

The max luminance is just max luminance, it's up to the display if it is able to maintain that or clip. The user can also adjust the display brightness, which will override the actual luminance. You can see this if you open the example in a dark room on a macbook and play with the display brightness. As far as I understand it, the luminance values are for the case where you have a fully calibrated reference hardware pipeline, in reality there are a bunch of things that happen between the rendered f16 output and the pixels lighting up on the display that will cause that to differ.

I don't really understand how to use the calibration example (am I supposed to google the values for my monitor?

You're just tweaking how bright paper white should be in a scene and how bright you want peak brightness to be. You can "calibrate" it, but most games let you tweak this yourself in game at runtime.

The max luminance left/right controls in the demo seem inverted to how I expect.

Right increases, left decreases. It's also increasing the range so the fact that paper white level (red) moves the other direction might be confusing you.

aevyrie added 5 commits January 16, 2026 00:41

First attempt at HDR output

3d2c0a0

Merge remote-tracking branch 'origin/main' into hdr-output

63896b0

# Conflicts: # crates/bevy_ui_render/Cargo.toml

Fix pipeline keys

15b5767

More pipeline fixes

c607de6

Fix SDR tonemapping

6a45fe1

aevyrie marked this pull request as draft January 17, 2026 07:25

alice-i-cecile added A-Rendering Drawing game state to the screen M-Release-Note Work that should be called out in the blog due to impact S-Waiting-on-Author The author needs to make changes or address concerns before this can be merged labels Jan 17, 2026

github-project-automation bot added this to Rendering Jan 17, 2026

alice-i-cecile added the C-Feature A new feature, making something new possible label Jan 17, 2026

aevyrie commented Jan 17, 2026

View reviewed changes

aevyrie marked this pull request as ready for review January 17, 2026 07:34

Fix wide gamut bloom

feb4cb9

JMS55 self-requested a review January 17, 2026 15:04

Commit shader

69c693c

Merge branch 'main' into hdr-output

0def855

aevyrie added M-Deliberate-Rendering-Change An intentional change to how tests and examples are rendered and removed M-Deliberate-Rendering-Change An intentional change to how tests and examples are rendered labels Jan 21, 2026

aevyrie added 2 commits January 20, 2026 19:48

Add HDR calibration example to readme

328c7c7

Fix lint

c8a35c8

jasmine-nominal suggested changes Jan 21, 2026

View reviewed changes

Uh oh!

HDR Display Output #22563

Are you sure you want to change the base?

HDR Display Output #22563

Conversation

aevyrie commented Jan 17, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Objective

Solution

Testing

Uh oh!

github-actions bot commented Jan 17, 2026

Uh oh!

aevyrie Jan 17, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Choose a reason for hiding this comment

Uh oh!

github-actions bot commented Jan 17, 2026

Uh oh!

johansigfrids commented Jan 17, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

github-actions bot commented Jan 19, 2026

Uh oh!

aevyrie commented Jan 21, 2026

Uh oh!

jasmine-nominal left a comment • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Choose a reason for hiding this comment

Uh oh!

jasmine-nominal Jan 21, 2026

Choose a reason for hiding this comment

Uh oh!

jasmine-nominal Jan 21, 2026

Choose a reason for hiding this comment

Uh oh!

jasmine-nominal Jan 21, 2026

Choose a reason for hiding this comment

Uh oh!

jasmine-nominal Jan 21, 2026

Choose a reason for hiding this comment

Uh oh!

jasmine-nominal Jan 21, 2026

Choose a reason for hiding this comment

Uh oh!

jasmine-nominal Jan 21, 2026

Choose a reason for hiding this comment

Uh oh!

jasmine-nominal Jan 21, 2026

Choose a reason for hiding this comment

Uh oh!

jasmine-nominal commented Jan 21, 2026

Uh oh!

jasmine-nominal commented Jan 21, 2026

Uh oh!

jasmine-nominal commented Jan 21, 2026

Uh oh!

jasmine-nominal commented Jan 21, 2026

Uh oh!

aevyrie commented Jan 21, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

4 participants

aevyrie commented Jan 17, 2026 •

edited

Loading

aevyrie Jan 17, 2026 •

edited

Loading

johansigfrids commented Jan 17, 2026 •

edited

Loading

jasmine-nominal left a comment •

edited

Loading

aevyrie commented Jan 21, 2026 •

edited

Loading